Wishing you the best with your exam and your journey ahead.

The fact that you have already owned and sold a rental property gives you a great experience to start from.In terms of the best place to invest - that is whatever place meets your criteria, goals and investing style.Personally flips have not been working as well for me lately, but when we get the right BRRRR deal those are still working well.

Just my two cents, best of luck on the journey! 

Whether you spend time networking, reading books, watching videos or connecting on bigger pockets or if you spend cash hiring a mentor, maybe partnering up with or doing free intern work for a real estate investor; whichever route you decide to go investing in yourself is one of the best investments you can make. 

It's the best of all worlds with regard to self-directed investing!

My gross income is a bit less than $7k (and I'm renting near top of market rates) with minimal repairs ($2k/y), but...1.

I am not in your area, but wish you the best of luck on this new journey! 

I'm a Realtor with a couple properties listed in Boise, ID and a neighboring town for my investor/client that are currently rented as co-living or rent-by-the-room and getting killer income. (7.3% - 9.5% Cap rate) So far, every inquiry has been baffled by the concept of co-living or rent-by-the-room and immediately ask if they're being run as a halfway-house (which they are not).

Finally, what’s the rate of return for alternative investments? 

When something goes wrong, you can find the best contractor for the job, who can make the repairs right away, and now your tenants are happy, and you have minimized the time you would have spent speaking to your tenants about the delay or fighting a warranty company.